Will Smith Faces No Charges After Oscar-Night Slap of Chris Rock

“I would like to publicly apologize to you, Chris. I was out of line and I was wrong. I am embarrassed and my actions were not indicative of the man I want to be.”

In rehearsals for the awards show, Mr. Rock didn’t tell the joke that led Mr. Smith to slap the comedian, people close to the production said.

Mr. Rock’s joke, a riff about Ms. Pinkett Smith’s short hair, also wasn’t on the teleprompter for the show, they said.

Ms. Pinkett Smith has said on social media that she has alopecia, a medical condition that causes hair loss. Representatives for Mr. Rock didn’t respond to a request for comment.

Later in the evening Mr. Smith won the Oscar for best actor for his performance in the drama “King Richard,” a biopic about

Richard Williams,

the father of tennis stars Venus and Serena Williams.

Mr. Smith also apologized to the Academy of Motion Picture Arts and Sciences, which puts on the Oscars; the producers of the show and its attendees and viewers; the Williams family; and “my King Richard Family.”

The Academy announced a formal investigation into the incident earlier Monday and condemned Mr. Smith’s actions. The group also shared organizational rules that show it has the power to revoke an Oscar after the fact. 

The Academy’s standards of conduct state that the organization can take disciplinary actions including revoking awards. The Academy can take less drastic measures, too, including private or public reprimand, and temporary or permanent loss of eligibility for future Oscars.

Mr. Rock declined to file a police report against Mr. Smith, according to the Los Angeles Police Department, which released a statement saying that it was aware of “an incident between two individuals” at the Academy Awards. “The incident involved one individual slapping another,” the statement read. 

After the ceremony, which drew more than 15 million viewers, Mr. Smith continued in the manner of any regular Oscar winner. He posed for photographs, smiling with children Willow, Jaden and Trey Smith, alongside Ms. Pinkett Smith. Ms. Pinkett Smith changed into a spangled gown the color of champagne. The family huddled close for an intimate photo portrait at the Vanity Fair Oscar party.  

During his acceptance speech, he apologized to the Academy, but not to Mr. Rock.

This wasn’t the first time Mr. Rock had fun at the expense of the couple. When the comedian hosted the 2016 Academy Awards he also made jokes about the pair, including questioning Mr. Smith’s high salary.

Mr. Smith’s family appeared to close ranks around him. His son, Jaden Smith, tweeted: “And That’s How We Do It.”

Some of the loudest critics of Mr. Smith’s slap were comedy professionals, including filmmaker Judd Apatow, stand-up comedian Jim Gaffigan and comedy personality Kathy Griffin.

At the ceremony, Mr. Smith appeared to be consoled by other celebrities in the room including Denzel Washington, Bradley Cooper and Tyler Perry. Tributes to him followed after the show, like this one from rapper Nicki Minaj, who said Mr. Smith was right to defend his wife. “This is what any & every real man feels in that instant,” she wrote on Twitter. “While y’all seeing the joke he’s seeing her pain.”

Video posted on social media from the Vanity Fair afterparty showed Mr. Smith clutching his Oscar, dancing and rapping along to his hit “Gettin’ Jiggy Wit It.” He was surrounded on three sides by guests holding up their phones to capture the moment as they danced along with him. 

Before the show, Mr. Smith posted to his Instagram pictures of himself and Ms. Pinkett Smith in jokey poses with the caption, “Me ‘n @jadapinkettsmith got all dressed up to choose chaos.” Later, Mr. Smith commented on the post: “You can’t invite people from Philly or Baltimore nowhere!!”

Will Packer, executive producer of the Oscars telecast, also made a joke about the incident when he tweeted, “Welp…I said it wouldn’t be boring #Oscars.”

—Omar Abdel-Baqui contributed to this article.

Write to Ellen Gamerman at ellen.gamerman@wsj.com and Joe Flint at Joe.Flint@WSJ.com